1. Field of the Invention
The present invention relates to a reproducing apparatus for reproducing information from recording elements on whose planar surfaces are formed very small pits.
2. Description of the Related Art
There is a magnetic reproducing apparatus for recording information in magnetization direction with respect to a magnetic recording medium by means of a magnetic head and for reproducing information by detecting the magnetization direction by means of the magnetic head. Applicants know an optical reproducing apparatus for recording information from pits with minor irregularities formed on the surface of a substrate and for reproducing information by a method in which the pits are radiated with light beams and the presence of pits is detected by variations in the intensity of the reflected light. The Applicants also know a photo-magnetic reproducing apparatus for arranging portions having a fixed magnetization direction in a recording medium (recording bits) and for reproducing information by a method in which a recording medium is radiated with light beams and the arrangement of the recording bits is detected by variations in the polarization direction of the reflected light.
The above-mentioned reproducing apparatuses have problems in that their ability to read out a magnetic head or light beams is limited, and the recording density cannot be increased markedly since pits and recording bits have a length measured in submicrons at the minimum.